In the related art, plane displayers are classified as active matrix displayers and passive matrix displayers based on the driving manners. The difference between an active matrix displayer and a passive matrix displayer lies in that an active element is provided in the circuit structure of the active matrix displayer. Generally, the active element is a thin film transistor. The active matrix displayer controls, through the thin film transistor, the regions such as the pixel region of the displayer to work.
However, the various thin film transistors in the circuit structure have different functions and usages. For the thin film transistors that play different roles in the circuit structure, the requirements on the characteristics or the parameters of the thin film transistors are also different.